David Ley, a vocal coach at University of Alberta in Canada has developed a technique using a handheld vibrator to stimulate the vocal chords to allow singers to sing more comfortably with a broader range. Apparently it started when one of his students was having trouble getting her voice back and need to relax the muscles in her larynx rather than rubbing fingers on her throat which can be an awkward feeling for some Ley found handheld vibrators that move at the same rate as human vocal chords and so far it has had remarkable effects with minimal side effects. Check the video for more.
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